To be certain, you should:
* Consult your owner's manual: This is the best resource for the exact location and specifics for your particular vehicle.
* Use a repair manual: A Haynes or Chilton manual for your year and model will have diagrams showing the air pump's location.
* Search online for "2005 Trailblazer air pump location" along with your engine type (e.g., "2005 Trailblazer 4.2L air pump location"). You might find images or videos showing the pump.
Caution: The air pump gets hot when operating. Be careful when locating and working near it.